3rd Generation Partnership Project (“3GPP” for short) Long Term Evolution-Advanced (“LTE-A” for short) is an enhancement of Long Term Evolution (“LTE” for short). An LTE-A system has a higher requirement on bandwidth than an LTE system, and supports a downlink peak data rate of 1 Gbit/s and an uplink peak data rate of 500 Mbit/s. To meet a requirement of LTE-A, the LTE-A system uses multiple technologies to improve the data rate. However, as wireless communications rapidly develops and an ultra-high rate service (for example, a high-definition video) emerges, a load on a wireless communications network becomes increasingly heavy. To better reduce the load on the network, a device to device (“D2D” for short) communications emerges. In this communication mode, terminals may directly communicate with each other without forwarding through an evolved NodeB, thereby offloading the evolved NodeB. With D2D communications, a spectrum resource can be better utilized, so as to improve spectrum utilization and the data rate, thereby reducing a load on the evolved NodeB.
In the prior art, a specific process in which user equipment (“UE” for short) obtains a resource is as follows: The UE monitors an available resource in a predefined cycle; if an idle resource is detected, the UE may select a resource and claim to use the resource in a currently claimed channel, and uses the resource to send data in a next cycle.
In a process of implementing the present invention, the inventor finds that the prior art has the following disadvantages:
In a predefined cycle, multiple UEs may claim a resource at the same time; when a resource claimed by another UE is the same as the resource claimed by the UE (a case in which different UEs claim a same resource), a conflict of the claimed resource occurs, which causes a relatively high delay of obtaining the available resource by the UE. Particularly, when there are a large quantity of UE and fewer idle resources, and a conflict probability is extremely high; in this case, the UE needs to claim multiple times so as to obtain the available resource, and therefore the delay of obtaining the resource by a user is higher.